The head of the largest union representing U.S. flight attendants slammed Delta Air Lines Wednesday for seeking a reduced quarantine period for “breakthrough” COVID-19 cases.

Sara Nelson, the president of the Association of Flight Attendants, criticized a proposal by Delta's CEO Ed Bastian to cut mandatory quarantine time down for breakthrough cases from 10 days to five. Nelson warned that if successful, these measures would "put flight attendants in a position to be forced to come back before they feel better.”

"I think that is the wrong move and the wrong message to send to the country at this time," Nelson told CNBC. "We are not happy about Delta's move to ask for this and think it is the wrong way to go."

The union represents 50,000 flight attendants, including employees at Delta, JetBlue and United Airlines, among others.

On Monday, Bastian reached out to Rochelle Walensky, director of the Centers for Disease Control and Prevention, to urge the agency to cut its mandatory quarantine period in half. His request was soon followed by a similar request from JetBlue CEO Robin Hayes the next day.

In his letter, Bastian expressed concern that the 10-day isolation period for the fully vaccinated could "exacerbate shortages and create significant disruptions" to its workforce. This position has been debated as more information emerges about the Omicron variant, but the CDC has not indicated if its position will change.

RELATED STORIES
CDC